New synthetic routes to beta-lactams have been developed and are being systematically studied in terms of scope and mechanism. These routes include the thermolysis of 4-azido-2-pyrrolinones, the cycloadditions of electron-deficient cumulenes to imines and formimidates, the thermolysis of cyclic diazo compounds, and the oxidation of 4-amino-2-pyrrolinones. It is anticipated that these methodologies will find utilization in the proposed synthesis of naturally occurring beta-lactams such as penicillin and cephalosporin. In addition to exploring new routes to beta-lactams, the synthetic utilization and biological properties of such products are also under investigation.